A case report of lymphangioleiomyomatosis with retroperitoneal masses in pregnancy.

Background: Lymphangioleiomyomatosis (LAM) is a rare, gradually advancing tumor of unknown origin. It is distinguished by the anomalous proliferation of pulmonary smooth muscle cells and predominantly manifests in women of childbearing age. In this study, we aim to present a noteworthy case of LAM accompanied by lymphangioleiomyoma in the retroperitoneal space during pregnancy, a scenario susceptible to misdiagnosis. Case presentation: A 31-year-old woman, facing an unintended pregnancy, presented during the 13th week with a cystic-solid mass exhibiting abundant blood signals in the pelvic cavity, as revealed by routine obstetrical ultrasound. Concurrently, her chest CT disclosed diffuse thin-walled cavities in both lungs. Despite the absence of clinical symptoms, the patient abandoned pregnancy and underwent a complete curettage. However, 24 days post-operation, she was readmitted for further assessment, revealing an enlargement of the mass encompassing the abdominal aorta and inferior vena cava, along with compression on the middle and lower segments of the ureter. After a multi-disciplinary discussion and patient explanation, an exploratory laparotomy was performed, resulting in the complete removal of the tumor. Intraoperative pathological examination and immunohistochemical staining indicated a retroperitoneal mass devoid of malignant evidence. The comprehensive morphologic and immunophenotypic features substantiated the diagnosis of lymphangioleiomyomatosis. The postoperative course was uneventful, culminating in the patient's discharge. Conclusion: The consideration of Lymphangioleiomyomatosis (LAM) with a retroperitoneal tumor is crucial in the differential diagnosis of pelvic and abdominal masses. The preoperative diagnosis of this tumor poses a challenge, as ultrasound or CT scans may not yield definitive results. Accurate diagnosis necessitates not only a pathological examination of the retroperitoneal mass but also the correlation with the patient's chest High-Resolution Computed Tomography (HRCT) findings and corresponding clinical manifestations. Optimal management involves radical surgery, with surgeons comprehensively factoring in both fetal and maternal conditions when formulating a treatment plan.